Machine for and method of marking metal articles



March 29, 1955 c TAYLQR 2,704,902

MACHINE F OR AND METHOD OF MARKING METAL ARTICLES Filed Aug. 18, 1951 3Sheets-Sheet l IN VEN TOR.

March 29, 1955 c. D. TAYLOR 2,704,902

MACHINE FOR AND METHOD OF MARKING MET-AL ARTICLES 3 Sheets-Sheet 2:

Filed Aug. 18, 1951 ASNQNI lliflwx INVIENTOR. Jj/Oi,

March 29, 1955 c. D. TAYLOR 2,704,902

MACHINE FOR AND METHOD OF MARKING METAL ARTICLES Filed Aug. 18, 1951 3Sheets-Sheet Z United States Patent MACHINE FOR ALJD METHOD OF MARKINGMETAL ARTICLES Charles D. Taylor, Hagerstown, Ind., assignor to PerfectCircle Corporation, Hagerstown, Ind., a corporation of IndianaApplication August 18, 1951, Serial No. 242,573

11 Claims. (Cl. 41-7) The invention relates generally to marking metalarticles and more particularly to marking metal articles having a coatedsurface such as a blued surface, tin-plated, or cadmium-plated surfaces,or surfaces having coatings known in the trade as Ferrox (a coating ofblack magnetic oxide, i. e. ferroso-ferric oxide) or Parco-Lubrite (aphosphate coating). 1

The general object of the invention is to provide a novel machine forand method of marking metal articles having coated surfaces of theforegoing character by which a relatively permanent marking is providedon the article without marring the surface thereof.

Another object is to provide a novel machine for and method of markingsuch coated metal articles by which a marking capable of withstandingoil is obtained, so that oil encountered in machining operations willnot obliterate the marking, nor will oil on the work pieces at the timeof marking interfere with the marking.

A further object is to provide a novel machine for and method of markingsuch coated metal articles by which the marking may be rapidly appliedto the article.

Other objects and advantages will become apparent from the followingdescription taken in connection with the accompanying drawings in which:

Fig. 1 is a side elevational view of a machine embodying the features ofthe invention and showing the air connections diagrammatically;

Fig. 2 is a plan view of the machine, partially in sec tion taken on theline 2-2 of Fig. 1;

Fig. 3 is a fragmentary sectional view taken on the line 33 of Fig. 2;

Fig. 4 is a fragmentary sectional view taken on the line 4-4 of Fig. land showing the marking means in its raised or inoperative position;

Fig. 5 is a view similar to Fig. 4, but showing the marking means inoperative position; and

Fig. 6 is a fragmentary View of an article showing, by way of example,the character of marking that may be placed thereon.

Difiiculty has been experienced heretofore in placing a marking on afinished surface of a metal article, which was permanent and which didnot mar the surfacein any way. Stamped markings can, of course, beplaced on metal surfaces, but they cause indentations in the surface andthus mar the surface in such a way that for some purposes such markingscannot be employed. Inks of different types have been used in suchcases, but the surface has to be absolutely clean before applying theink. Oil on the surface, such as remains after some machiningoperations, prevents marking in this manner. Moreover, the ink isreadily wiped off and obliterated and will not withstand oil encounteredin subsequent machine operations.

The present method provides a substantially permanent marking on coatedmetal surfaces without marring the surface. Thus, the present inventionis applicable for marking surfaces which have been blued, tinplated,cadmium-plated, or which have been given coatings known in the trade asFerrox (a coating of black magnetic oxide, i. e. ferroso-ferric oxidelorParco-Lubrite (a phosphate coating). The invention, however, is notlimited to these specific coatings, but can be used with any othersimilar types of coatings. There are, of course, numerous types ofarticles where marking of this character is desirable. One instance is'in the case of piston rings such as are employed inv internalcombustion engines or in other piston and cylinder devices.

2,704,902 Patented Mar. 29, 1955 The invention comprises generally amethod of and machine for producing markings of this character byimpregnating the coated surfaces of such metal articles with arelatively soft metal in areas defining the markings desired. Thus,letters, numerals, or other characters may be marked on an article byimpregnating a soft metal into the coating in the form of such letters,numerals, or other characters. To effect such impregnation of thecoatings, a strip or piece of foil of such soft metal is placed upon thesurface to be marked, and a tool or type bar having characters on itsface of substantially the size and shape of the marking is pressedagainst the foil to clamp the latter between the tool and the work. Thetool is then given a vibratory rubbing movement parallel to the surfaceof the work. Such vibratory movement is preferably circular, and as aresult thereof, some of the metal from the foil is forced into thecoating to form a marking substantially corresponding in size and shapeto the characters on such tools. The various lines forming suchcharacters, of course, will be slightly broader than the width of suchlines on the tool, due to the vibratory motion of the tool, but suchvibratory motion is small compared to the width of the lines of thecharacters on the tool so that such lines are not greatly enlarged ordistorted by the increase in width.

The marking thus obtained on a coated surface of this character issubstantially permanent in character and at least will remain on thearticle so long as there is any coating left in the area of marking.Such marking is not in any way affected by oil during subsequentmachining operations and may be applied to an article even when thelatter is covered with a film of oil from previous machining operations.Furthermore, the marking may be rapidly performed and does not requireany time subseuent to its application to dry.

The preferred form of the machine for applying such marking, shown inthe drawings, comprises a base or work support 10 which, in'thisinstance, comprises a fiat block of metal adapted to rest on a bench.The upper surface of the work support 10 is adapted to receive the workwhich is here illustrated as being a piston ring 11 lying fiatwisethereon. Extending upwardly above the rear portion of the base 10 is themarking means and the means for supporting the soft metal foil-inposition for application to the work piece. Preferably, the markingmeans and the foil supporting means are carried by a pair of upstandingposts 12 located at the rear of the base 10 and having their lower endssecured therein as by set screws 9. The posts 12 are laterally spacedfrom each other and slidably support a head or tool support 13. The toolsupport 13 is adapted to be moved toward and from the work by aid underpressure and, to this end,

the tool support comprises a cylinder 14 having a pair of tubularportions 15 at its sides, through which the posts 12 extend. At itslower end, the tool support is provided with a slot 16 in which a typebar or tool 17 is secured as by a set screw 18. The tool or type bar 17extends slightly below the lower end of the tool support 13 and has onits lower face the desired characters indicated at 20. These characters20 project from the lower face of the tool bar 17 and are ofsubstantially the same size and shape as the marking desired on the workpieces, although the lines of which the characters may be formed areslightly narrower than the lines of the ultimate marking.

The soft metal foil is preferably supplied in the form of a roll 21supported and partially enclosed by a sheet metal cover structure 22. Inthe present instance, the coil or roll of foil is shown as provided witha core 23 through which an axle 24 extends, the latter being mounted inslots 25 in the'side walls of the supporting structure 22. The latter ismounted on the upper end of the tool support 13. The supportingstructure 22 is also preferably provided with a wiper 26 which bearsagainst the surface of the metal foil as it is drawn 01f the roll sothat all foreign matter'is. wipedvoif themetal foil before it is appliedto the work. The free endof the foil extends downwardly from the frontof theroll and is drawn rearwardly under the tool 17, so that it will bepressed against the work when the tool is moved into operative position.

To move the tool toward and from the work, air operated means isemployed as .heretofore mentioned. In the present instance, theair-operated means comprises the cylinder 14 co-operating with a piston30 carrying packing 31 engaging the walls of the cylinder 14. The piston30 is of two-part construction comprising a lower member 32 threaded onthe lower end 33 of a piston rod 34, the other member of the piston,indicated at 35, being clamped between the member 32 and a shoulder 36formed on the piston rod 34. In this instance, the piston remainsstationary during operation of the device, while the cylinder moves, andthe piston rod 34 has a reduced upper end 40 extending through a bridge'41 spanning the space between the post 12 and secured to the posts asby nuts 42. The reduced upper end 40 of the piston rod 34 is secured tothe bridge41 as by means of 'a nut 43.

In operation, when air under pressure is admitted to the cylinder14below the piston 30, the tool support 17 will be moved downwardly topress the type bar or tool as well as the metal foil against the Work.When air under pressure is admitted to the upper end of the cylinder 14above the piston 30 and the lower end of the cylinder is connected toexhaust, the work support 13 will be moved upwardly. Thus, the tool maybe moved toward the work and from the work with the foil interposedbetween the tool and the work.

As heretofore mentioned, when the tool and the foil are pressed againstthe work, the tool is also vibrated in a direction parallel to thesurface of the work which is to be marked. This produces a rubbingaction while the foil is pressed against the Work and results inimpregnating the coated surface of the article with metal from the foil.The vibratory motion imparted to the tool is preferably generallycircular in character and to accomplish this result, a pair of vibratorsare secured to the toolsupport 13 to produce a resultant circularmovement. As shown in the drawings, the tool support 13 is provided atone side with a laterally extending lug 44 and at its rear with anotherlug 45. Secured to the lugs 44 and 45 are vibrators 46 and 47. In thisinstance, the vibrators 46 and '47 are of the-air-operated type and tendto produce a vibratory movement longitudinally thereof. Thus, theyimpart a vibratory motion in two directions to the tool support 13, theposts 12 loosely fitting in the tubular portions of toolsuppo'rt sothatthe latter is free to vibrate. Since the vibrators are positioned atright angles to each other and areoperated simultaneously, theresultan't motion given to'the tool support is circular in character, sothat the tool 17 is given a circular rubbing movement parallel to thesurface on the work piece to be marked.

It has been found that; after each marking operation,

'theparticular portion of'thef'oil applied to the work piece isunsuitable for further marking, although very little of the metal fromthe foil has been impregnated into the surface'of the article. Therubbing action of the tool, while it does not puncture or perforate themetal foil, apparently causes a hfardening'of the foil, therebyrendering it unsuitable for further. use. Consequently, the foil isshifted relative to the work, so that a new portion of foil is availablefor the ring marking operation.

As heretofore mentioned, the free end of the foil from the roll 21extends downwardly over the front of the work support 13- and'thentierearwardly under the tool 17, as indicated at 50 in Fig. l. Tofeed thefoil, a feeding device indicated generally at 51 is provided. Suchfeeding device, in thepresent instance, is'illu'strated as comprising abracket 52 secured'to and extending'rearwardly from the base or worksupport 10; The free end 50 of the foil extends rearwardly over the base52, and over it is mounted a movable tongue 53 having a sharp lower edge54 adapted move theztongue .53 in this manner, an air operated, pistonand cylinder deVice'indicat'ed'atSS is provided. a The piston of thedevice 55 has apiston rod' 56 upon the free end of to dig .into inefofland; shift it rearwardly along 'the' bracket 52. When the air'presshreis rel eased from the device 55, the piston rod 56 is retractedbyaspring' (not shown) and the tongue 53 rides freely over the foil. Tolimit the extent to which the foil is fed on each stroke of the pistonrod 56, a bridge 57 is mounted on the outer or rear end of the bracket52, so that the foil can pass thereunder, and a stop screw 53 isthreaded in the bridge 57 to provide an adjustable abutment limitingrearward movement of the piston rod 56.

The base 10 is preferably provided with a work locating means so thatthe marking maybe placed in the same location on each piece of Work. Inthe present instance where piston rings are being marked, the worklocating means comprises a pair of supports 69 of elongated form,adapted to lie flatwise on the base 10 and provided with longitudinalslots through which screws 61 provided with wing nuts 62 extend. Thesupports thus may be clamped to the base and are adjustable bothlongitudinally and angularly about the screws 61, so that the workpositionin' means may be adapted for rings of different diameters.Extending between the supports 66 is a flexible metal band '63 which is"held in an arcuate form by'the supports 60. The band 63 at each of itsends is provided with an attaching member 64 by which the band issecured to the supports 60. Since it is desirable to place the markingon each piston ring at a set distance from one end of the ring formed bythe gap therein, one of the attaching members 64 is provided with afinger portion 65 adapted to extend into the gap of the ring. Thus, whena ring is being put into place for marking, it is placed in abutment,

with the band 63 and one end of the ring engages the finger portion 65.a

As heretofore mentioned, the means for moving the work support 13, aswell as the vibrators 46 and 47 and the foil feeding device 51, are alloperated by air under pressure. The supply of such air to these variousdevices thus may be co-ordinated into a single air supply systemillustrated diagrammatically as a part of Fig. 1. As shown in thisfigure, air under pressure .is supplied from a suit able source througha pipe and it then is preferably passed through a filter 71 and alubricator 72. From there, the air passes to a three-way valve 73 whichmay be of the type adapted to be actuated by foot. For operating thevarious parts of the machine, the valve 73 is connected by a pipe 74 totwo branch lines 75 and 76. In .each of these branch lines is a pressureregulator 77 and a gauge 78. The branch line 75 is connected to operatethe two vibrators 46 and .47 while the branch line 76 is connected tosupply air to the lower end of the cylinder 14 for moving the tool 17downwardly into engagement with the foil. The branch line 76 alsosupplies air to the piston and cylinder device 55 for feeding the foilrearwardly to bring a new portion thereof under the tool 17. Since thevibrators 46 and 47, the lower part of the cylinder 14, and the pistonand cylinder device 55 for feeding the foil all are connected with theline 74, the valve 73 when it connects the source with the line 74 thuscauses the tool to be moved downwardly, the foil to be fed through onestep and the two vibrators to operate. Mark in g of the work piece isthereby effected.

Thevalve 73 is also adapted to be shifted to a position where the line74 is cut off from the source 70 and .a 'line '80 is connected thereto.The line 80 leads to the upper part of the cylinder 14 and when airunder pressure is supplied thereto, the tool support 13 will be raisedto move the tool 17 away from the work. The valve 73.may also be movedto an intermediate position which it normally assumes, in which positionneither the line 74 nor the line 80 are connected to the source 70.

Asian example of the size of the marking contemplated, .a markingwhichhas been found suitable for pistonIrings involves the use ofcharacters in which the various component lines haveawidth on the orderof .008 of an inch. The extent of vibration utilized with lines of thiswidth was .002 to .0025 of an inch. Thus, the width of the componentlines of the marking would be on the order of .010 of an inch, so thatthe characters on the tool have substantially the same size and shape asthe marking. Thefoil used was .002 of an inch in thickness and wasaluminum of the grade known in the trade as fullann'ea'led. Theinvention, however, is obviously not limited to these particular"dimensions, nor to use of this particular metal for the foil. 'Othersoft metals such .as copper couldhe used, and characters of-differentwidths of, lines c'ould'of course be formed. t is obvious, "too,'thatwi'tliniarkings" composed of lines of greater width, at

greater range of vibration may be employed without unduly distorting thecharacters.

From the foregoing, it is apparent that I have prov ded a novel methodof and machine for marking metal art cles having coated surfaces of thecharacter described. Since the material from the foil is impregnatedinto the coating on the metal surface, a relative permanent marking isthereby obtained. Moreover, there is no marring of the material surfacesince insufficient pressure is applied to the tool to cause anyindentation on the surface of the work piece. In the case of pistonrings, it was found that a downward pressure on the tool anywhere fromten to forty pounds, depending upon the extent of the marking, wassufiicient. It therefore appears that the rubbing movement effected bythe vibrators causes the impregnation of the metal of the foil into thesurface. The pressure apparently merely holds the foil in close contactwith the surface of the article. Oil encountered in machining operationsdoes not affect the marking, and it has been found that, even if a filmof oil is on the article at the time of marking, it does not interferewith proper impregnation of the foil into the surface.

i claim:

1. The method of marking a surface of a metal article having animpregnatable surface coating, comprising placing a piece of soft metalfoil on said surface, pressing a tool having a foil engaging faceprovided with characters of substantially the size and shape of themarking against the exposed face of said foil with a pressure which isinsufficient to indent said surface, the foil being softer than saidcoating and said tool, and vibrating said tool in a direction parallelto said surface while the tool is held under such pressure whereby themetal surface is provided with the marking solely by impregnation ofsaid coating with the foil and without indentation or covering of saidsurface.

2. The method of claim 1 further characterized in that said tool isvibrated with a generally circular motion parallel to said surface.

3. The method of claim 1 further characterized in that said tool isvibrated in two directions perpendicular to each other and parallel tosaid surface.

4. A marking machine for marking a surface of a metal article having animpregnatable surface coating, comprising a work support, a tool havingcharacters on its face of substantially the size and shape of themarking, means for feeding a strip of soft metal foil between the tooland the work, guide means mounted on said work support, a tool supportcarrying said tool and slidably supported by said guide means formovement toward and from said work support, means for moving said toolsupport toward the work to clamp the foil between the tool and the work,and vibrating means mounted on said tool support for vibrating the toolparallel to the Work.

5. The apparatus of claim 4 further characterized in that said machineis also provided with means for supporting a coil of soft metal foiladjacent said tool with the foil being adapted to extend between thetool and the work, and means is also provided for intermittently feedingsaid foil to place a new portion of foil between the toolkand the workeach time the tool is moved toward the wor 6. A marking machine formarking a surface of a metal article having an impregnatable surfacecoating, comprising a work support, a tool having characters on its faceof substantially the size and shape of the marking, means for feeding astrip of soft metal foil between the tool and the Work, a pair of postsmounted on said Work support, a tool support carrying said tool andslidably mounted on said posts and including pneumatic piston andcylinder means for moving the tool support toward the work to clamp tofoil between the tool and the work, and vibrating means mounted on saidtool support for vibrating the tool parallel to the work.

A marking machine for marking a surface of a metal article having animpregnatable surface coating, comprising a work support, a tool havingcharacters on its face of substantially the size and shape of themarking, means for feeding a strip of soft metal foil between the tooland the work, a pair of posts mouted on said work support, an aircylinder slidably mounted on said posts and carrying said tool andmovable toward the work to clamp the foil between the tool and the work,a piston mounted in said cylinder and rigidly supported by said posts,and vibrating means mounted on said cylinder for vibrating the toolparallel to the work.

8. A marking machine for marking a surface of a metal article having animpregnatable surface coating, comprising a work support, a tool havingcharacters on its face of substantially the size and shape of themarking, means for feeding a strip of soft metal foil between the tooland the work, a pair of laterally spaced posts mounted on said worksupport, an air cylinder located between said posts and having a pair ofsleeve portions slidably mounted on said posts, said cylinder carryingsaid tool and being movable toward the work support to clamp the foilbetween the tool and the work, a bridge rigidly connecting the upperends of said posts, a piston mounted in said cylinder and having apiston rod rigidly connected to said bridge, and vibrating means mountedon said cylinder for vibrating the tool parallel to the work.

9. A marking machine for marking a surface of a metal article having animpregnatable surface coating, comprising a work support, a tool havingcharacters on its face of substantially the size and shape of themarking, means for supporting a coil of soft metal foil adjacent saidtool with the foil extending between the tool and the work, airoperatedmeans for moving the tool toward and from the work, air-operated meansfor intermittently feeding said foil to place a new portion of foilbetween the tool and the work, air-operated vibrating means forvibrating the tool parallel to the work, a source of air under pressure,and valve means arranged when in one position to connect said sourcewith said tool moving means to move the tool toward the work and withsaid foil feeding means to place a new portion of foil between the tooland the work and with said vibrating means, and when in another positionto move the tool away from the work.

10. A marking machine for marking a surface of a metal article having animpregnatable surface coating, comprising a Work support, a tool havingcharacters on its face of substantially the size and shape of themarking, means for feeding a strip of soft metal foil between the tooland the work, a pair of posts mounted on said work support, a toolsupport carrying said tool and slidably mounted on said posts andincluding means for moving the tool support toward the work to clamp thefoil against the work by pressing the tool thereagainst, and means forvibrating the tool support parallel to the work and transversely of saidposts, said tool support loosely engaging said posts to permit oflimited vibration relative thereto.

1 A marking machine for marking a surface of a metal article having animpregnatable surface coating, comprising a work support, a tool havingcharacters on 1ts face of substantially the size and shape of themarking, means for feeding a strip of soft metal foil between the tooland the work, a pair of posts mounted on said work support, a toolsupport carrying said tool and slidably mounted on said posts andincluding means for moving the tool support toward the work to clamp thefoil against the work by pressing 'the tool thereagainst, and means foreffecting limited vibration of the tool support parallel to the Work andtransversely of said posts, said posts having a loose fit in at leastone of said supports wherebv to permrt said limited vibration of thetool support.

References Cited in the file of this patent UNITED STATES PATENTS845,730 Marshall Feb. 26, 1,898,782 Littlefield Feb. 21, 193; 2,259,255Levine Oct. 14, 1941 2,326,603 Barish Aug. 10, 1943 2,326,604 BarishAug. 10, 1943 2,427,358 Kovach Sept. 16, 1947 2,547,602 Schmitt Apr. 3,1951 2,573,570 Howard Oct. 30, 1951

